1. Field of the Invention
The present invention relates to a toilet bar suitable for topical application for cleansing the human body, such as the skin and hair. In particular, it relates to a toilet bar composition that is mild to the skin and which also exfoliates the skin.
2. The Related Art
Exfoliating toilet bars are well known. However, the majority of them are very irritating to the skin due to the fact that they are soap based, have high levels of harsh or marginally effective exfoliants, low levels of moisturizers, or some combination of the preceding. Certain prior art toilet bars with high levels of mild synthetic surfactant (xe2x80x9cSyndetxe2x80x9d) and high levels of moisturizers have been described as optionally having exfoliant particles or beads such as sic polyoxyethylene (polyethylene) beads, walnut shells, and apricot seeds, and the like. See e.g. U.S. Pat. Nos. 6,376,441; 6,342,470; 6,384,000; and 6,074,998. Surprisingly it has been found that mild toilet bars having one or more syndet surfactants, one or more moisturizers, and exfoliants of a specific particle size range provide the user with enhanced moisturization and exfoliation simultaneously. This causes the user""s exfoliated skin to appear fresh and healthy as it removes the dull layer of dead skin, accompanied with deep cleansing leading to less clogged pores while at the same time moisturizing the skin to minimize irritation and dryness as shown by various art recongnized techniques described below.
While not wishing to be bound by the following skin treatment theories, Applicants believe that exfoliation improves skin cleansing by helping to mechanically remove dirt and oil from the skin. Exfoliation also is believed to aid the process of desquamation. Desquamation is a natural process by which corneocytes are removed from the stratum corneum, which is the top layer of skin cells. Corneocytes are simply the cells that comprise the stratum corneum, and they are constantly being removed as the skin regenerates. Exfoliation aids in removing the flaky corneocytes that are ready to detach from the stratum corneum, and so promotes smoother, less flaky skin.
Other potential health benefits to exfoliation in addition to improved scale (flake) removal and oil removal, as suggested above, are reduction in bacteria on the skin, and increased blood flow to the skin due to the mechanical stimulation.
The inventive bar under actual use conditions is expected to show improvements in skin softness, skin smoothness, and similar consumer perceived benefits such as exfoliation efficiency, mildness, moisturization efficiency, deposition efficiency, cleansing efficiency, and a bar property such as skin abrasiveness, etc. based on changes from the baseline for these measurements using toilet bars without the inventive composition as quantified using the test methods described below.
In one aspect the present invention is a toilet bar, having:
a) a cleansing base including about 20 to 60% by wt. of one or more Syndet surfactants;
b) about 10 to 50% by wt. of a moisturizer; and
c) exfoliant particles wherein at least 25% by wt. of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns.
In another aspect of the invention is a toilet bar made by a process including the steps of:
(a) providing at least one synthetic surfactant, at least one moisturizer, and at least one exfoliant;
(b) mixing the ingredients of step (a) to form a product preblend, at or above a temperature sufficient to render the preblend flowable, until the preblend is substantially uniform, wherein the exfoliant, and a substantial portion of the at least one or more moisturizers is excluded from the preblend;
(c) cooling the resulting product preblend;
(d) optionally milling or refining the cooled product preblend to form pellets;
(e) blending the exfoliant with the substantial portion of one or more of the moisturizers not added to the product preblend formed in step (b) or (c) to form an exfoliant preblend;
(f) mixing the exfoliant preblend with the cooled product preblend in a solids blending device;
(g) refining the product of step (f) at least once; and
(h) extruding and stamping the product into toilet bars.
In another aspect of the invention is a method for simultaneously exfoliating and moisturizing the skin comprising the steps of:
a) providing a bar including
i) a cleansing base including about 20 to 60% by wt. of one or more Syndet surfactants;
ii) about 10 to 50% of a moisturizer; and
iii) exfoliant particles wherein at least 25% by wt. of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns;
b) adding sufficient water to wet the bar and the skin;
c) applying the bar to the skin;
d) rubbing the bar onto the skin for a time sufficient to remove dead skin cells and coat the underlying skin with at least one moisturizer.
In a further aspect of the invention is a method for providing the user with a variable level of exfoliation and moisturization on different regions of the body, including the steps of:
(a) providing a toilet bar, wherein the bar includes
1. a cleansing base including about 20 to 60% by wt. of one or more Syndet surfactants;
2. about 10 to 50% of a moisturizer; and
3. exfoliant particles wherein at least 25% by wt. of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns;
(b) moistening the bar; the body or both;
(c) rubbing the bar on user selected areas of the skin for a time sufficient to remove dead skin cells where substantial exfoliation is desired;
(d) adding sufficient water to the bar to form a lather;
(e) rubbing the lather onto user selected areas of the skin where moisturization without substantial exfoliation is desired for a time sufficient to coat the underlying skin with at least one moisturizer; and,
(f) wherein steps (c) to (e) may be carried out in any sequence by the user.